Reducing Yarn Hairiness with an Air-Jet Attachment During Winding

The winding process tends to promote yarn hairiness, a detrimental effect that can be significantly reduced by adding a properly arranged air-jet nozzle. This paper examines the mechanisms of hairiness reduction with an air jet during winding. The results indicate that the direction of the majority of protruding fibers and that of the air vortex play an important role. They also suggest that yarn hairiness can be best reduced if the gyrating air current lowers the twist level before the yam enters the jet, and if the air flow spirals along the yarn in a general direction opposite that of the yarn traverse to suppress the majority of protruding fiber ends. Wrapping of protruding fiber ends around the yarn and removal of “wild fibers” by the swirling air current are believed to be responsible for the reduction in yarn hairiness, and tucking of fiber ends into the yarn structure may also occur under certain conditions.